A physical impact to the head of a person may cause serious injury or death. To reduce the probability of such consequences, protective gear, such as a helmet, is often used in activities that are associated with an increased level of risk for a head injury. Examples of such activities include, but are not limited to, skiing, snowboarding, bicycling, rollerblading, rock climbing, skate boarding, and motorcycling.
A helmet may include one or more holes that allow air to reach the head of a wearer. Such a feature enhances comfort for the wearer and may also reduce the likelihood of heat-related injuries. However, these holes may also weaken the ability of a helmet to protect the head against certain types of physical impact.